Somatosensory evoked potentials recorded from DBS electrodes: the origin of subcortical N18.

The different peaks of somatosensory-evoked potentials (SEP) originate from a variety of anatomical sites in the central nervous system. The origin of the median nerve subcortical N18 SEP has been studied under various conditions, but the exact site of its generation is still unclear. While it has been claimed to be located in the thalamic region, other studies indicated its possible origin below the pontomedullary junction. Here, we scrutinized and compared SEP recordings from median nerve stimulation through deep brain stimulation (DBS) electrodes implanted in various subcortical targets. We studied 24 patients with dystonia, Parkinson's disease, and chronic pain who underwent quadripolar electrode implantation for chronic DBS and recorded median nerve SEPs from globus pallidus internus (GPi), subthalamic nucleus (STN), thalamic ventral intermediate nucleus (Vim), and ventral posterolateral nucleus (VPL) and the centromedian-parafascicular complex (CM-Pf). The largest amplitude of the triphasic potential of the N18 complex was recorded in Vim. Bipolar recordings confirmed the origin to be close to Vim electrodes (and VPL/CM-Pf) and less close to STN electrodes. GPi recorded only far-field potentials in unipolar derivation. Recordings from DBS electrodes located in different subcortical areas allow determining the origin of certain subcortical SEP waves more precisely. The subcortical N18 of the median nerve SEP-to its largest extent-is generated ventral to the Vim in the region of the prelemniscal radiation/ zona incerta.

Microelectrode recording and hemorrhage in functional neurosurgery: a comparative analysis in a consecutive series of 645 procedures.

OBJECTIVE: Functional stereotactic neurosurgery including deep brain stimulation (DBS) and radiofrequency lesioning is well established and widely used for treatment of movement disorders and various other neurological and psychiatric diseases. Although functional stereotactic neurosurgery procedures are considered relatively safe, intracranial hemorrhage resulting in permanent neurological deficits may occur in 1%-3% of patients. Microelectrode recording (MER) has been recognized as a valuable tool for refining the final target in functional stereotactic neurosurgery. Moreover, MER provides insight into the underlying neurophysiological pathomechanisms of movement disorders and other diseases. Nevertheless, there is an ongoing controversy on whether MER increases the risk for hemorrhage. The authors aimed to compare the risk of hemorrhage in functional stereotactic neurosurgical procedures with regard to the use of MER. METHODS: The authors performed a comparative analysis on a consecutive series of 645 functional neurosurgery procedures, including 624 DBS surgeries and 21 radiofrequency lesionings, to evaluate whether the use of MER would increase the risk for hemorrhage. MER was performed in 396 procedures, while no MER was used in 249 cases. The MER technique involved the use of a guiding cannula and a single trajectory when feasible. Postoperative CT scans were obtained within 24 hours after surgery in all patients and screened for the presence of hemorrhage. RESULTS: Twenty-one intracranial hemorrhages were detected on the postoperative CT scans (3.2%). Of the 21 intracranial hemorrhages, 14 were asymptomatic and 7 were symptomatic. Symptoms were transient except in 1 case. There was no statistically significant correlation between hemorrhage and the use of MER at any site (subdural, ventricle, trajectory, target, whether asymptomatic or symptomatic). There were 4 cases of symptomatic hemorrhage in the MER group (1%) and 3 cases in those without MER (1.2%). CONCLUSIONS: Intraoperative MER did not increase the overall risk of hemorrhage in the authors' experience using primarily a single MER trajectory and a guiding cannula.

Use and Acceptance of Drinking Fountains: A Pilot Study in Two Secondary Schools in Dortmund, Germany.

(1) Background: Water drinking is essential to reduce obesity in children, but effective means for implementation remain controversial. Our study assesses students' and teachers' use of and attitudes towards drinking fountains in two urban secondary schools. (2) Methods: In a cross-sectional study, answers from students and teachers to a 28- and 19-item questionnaire, respectively, containing closed- and open-ended questions and short interviews with the schools' two principals were described and analysed using the question-specific number of responses as the denominator. (3) Results: Questionnaires of one hundred sixty-two students and ten teachers were analysed; 36.1% of students responded. Students viewed the schools' two fountains as a good idea (73.3%, n = 118), recommended them to other schools (73.1%, n = 117), and felt able to distinguish healthy from unhealthy drinks (70.5%, n = 110). In contrast, 55.7% (n = 88) reported using the fountains regularly; over a week, 39.8% (n = 47) used them less than once; 26.3% (n = 31) used them one to two times. Only about a third (26.5%, n = 43) reported consuming more water since the fountains' installation. Teachers' responses were similar to students'; principals stressed planning and costs. (4) Conclusions: A discrepancy between a good attitude towards and actual use of drinking fountains may exist; school communities may need to look for measures to overcome it.

"I Need to Be the First One with a Different Approach and to Make a Difference to the People": A Mixed Methods Pilot Study on Non-Physician Clinicians Training in Malawi.

Purpose: To improve child health care depends on the availability of sufficient numbers of skilled healthcare workers. To achieve this, the German Society of Tropical Paediatrics & International Child Health supported the existing three-year Bachelor of Science in Paediatrics and Child Health training for Clinical Officers, a non-physician clinician cadre, from 09/2017 to 08/2019. This study aims to evaluate the project to inform forthcoming training. Methods: All 17 students who were in training took part in this study. Quantitative data collection took place between 01/2018 to 06/2019 using the post-self-assessment bloc course survey, Research Self-Efficacy Scale (RSES), and Stages of Change (SOC) model. Students and key informants participated in three focus group discussions and five in-depth interviews during April 1-10, 2019. Results: Students mostly perceived bloc course contents "At their level" (92%) and "Very important/relevant" (61%) with "Good quality" teaching (70.5%). The mean (SD) score for RSES (10-point scale) was 9.10 (0.91). The SOC (4-point scale) scores were higher for "Attitude" and "Intention" statements than "Action". Students found the program well-paced, felt that their clinical knowledge and skills had improved, and valued the acquired holistic disease management approach. They reported increased confidence and being more prepared for leadership roles in their future work. The involvement of international teachers and supervisors enriched their global perspectives. Conclusion: Students improved their clinical and non-clinical skills, developed self-efficacy and attitudes toward research, and were confident to build and utilize their networks. These transformative experiences could facilitate the development of change agents among current and future trainees.

Global child health in higher education in Germany: a mixed-methods study.

BACKGROUND: Germany has an ambitious global health strategy, yet its universities provide few opportunities for global child health researchers. Improved understanding of the reasons and the academic role of global child health is needed. OBJECTIVE: The objective of this study is to offer insights into Germany's academic global child health landscape by describing the actors and their priorities in research and education and by analysing perceived barriers and opportunities. METHODS: We used a sequential exploratory mixed-method design. Participants were selected purposively to represent German global child health academics. Information was gathered first from a 33-item online survey and from interviews conducted four to six months post-survey. Surveys were analysed descriptively. A joint thematic approach using content analysis was used to analyse interview transcripts. RESULTS: Four categories emerged: training and professional orientation; professional realities; representation and advocacy, and barriers. Of the 20 survey participants (median [IQR] age 55 years [17], five female), seven agreed to be interviewed. Research experiences abroad shaped individuals' career choices in global child health. They engaged in global child health education, primary health care and access to health services, frequently in clinical and humanitarian settings, but spent little time on global child health-related activities. Participants were active and valued in international networks and keen to extend their activities. Yet they felt under-represented academically and reported multiple structural and individual barriers in Germany. They perceived a lack of leadership positions, career paths, funding opportunities, and institutional and project support which limits academic advancement. CONCLUSIONS: Germany's global child health experts are motivated to engage with global child health-related topics but face difficulties in advancing academically. Academic actors may need to intensify research and training efforts in order to expand global child health's scientific base in Germany.

Adapting teaching and learning in times of COVID-19: a comparative assessment among higher education institutions in a global health network in 2020.

BACKGROUND: This research examines the ways in which higher education institutions (HEIs) across the tropEd Network for Education in International Health (tropEd) began to adapt their teaching and learning approaches in response to the COVID-19 pandemic in 2020. Already during this early phase of the pandemic HEIs' responses demonstrate global health approaches emphasising cooperation and communication, rather than national health driven strategies that emphasise quarantine and control. Key lessons learnt for multiple dimensions of teaching and learning in global health are thus identified, and challenges and opportunities discussed. METHODS: Data collection includes a cross-sectional online survey among tropEd member institutions (n = 19) in mid-2020, and a complementary set of open-ended questions generating free-text responses (n = 9). Quantitative data were analysed using descriptive statistics, textual data were analysed using a Framework Analysis approach. RESULTS: While early on in the pandemic the focus was on a quick emergency switch to online teaching formats to ensure short-term continuity, and developing the administrative and didactic competence and confidence in digital teaching, there is already recognition among HEIs of the necessity for more fundamental quality and longer-term reforms in higher education in global health. Alongside practical concerns about the limitations of digital teaching, and declines in student numbers, there is a growing awareness of opportunities in terms of inclusivity, the necessity of cross-border cooperation, and a global health approach. The extent to which the lack of physical mobility impacts HEI programmes in global health is debated. CONCLUSION: The COVID-19 pandemic has brought about preventive measures that have had a considerable impact on various dimensions of academic teaching in global health. Going forward, international HEIs' experiences and response strategies can help generate important lessons for academic institutions across different settings worldwide.

The pathophysiology of chronic subdural hematoma revisited: emphasis on aging processes as key factor.

Chronic subdural hematoma (CSH) affects mostly elderly subjects. Previously, pathophysiological concepts suggested that CSH is secondary to degradation of subdural collections of blood and its products exerting merely a mass effect on the underlying brain. During the last decades, however, new insights into the pathogenetic mechanisms urge us to reconsider such a simplistic view. Here, we critically review novel pathophysiological, imaging, interventional, and medical treatment aspects and establish an integrative concept of the pathogenesis of CSH stressing the role of age as key factor. Trauma is considered a trigger event that unleashes a cascade of immunological and angiogenic age-dependent responses. These are associated with hypervascularization of the outer hematoma membrane, rebleeding, and exsudation which are crucial determinants for further development and propagation of CSH. Neurosurgical evacuation of the hematoma has long been thought the only viable treatment option, and it is still the method of choice in the majority of cases. Only more recently, embolization of the middle meningeal artery has been introduced as an alternative to surgery, and pharmacological treatment options are being investigated. Persons with advanced age trauma and other trigger events encounter a repair system with characteristics of senescence. This repair system implies a dysfunctional secretory phenotype of senescent cells and results in an insufficient repair process including chronic inflammation and fibrosis. Increased knowledge about the pathomechanisms of CSH will inform future studies and open new perspectives for its treatment and possibly also for its prevention.

Measuring and monitoring child health and wellbeing: recommendations for tracking progress with a core set of indicators in the Sustainable Development Goals era.

Although great improvements in child survival were achieved in the past two decades, progress has been uneven within and across countries, and the COVID-19 pandemic threatens to reverse previous advances. Demographic and epidemiological transitions around the world have resulted in shifts in the causes and distribution of child death and diseases, and many children are living with short-term and long-term chronic illnesses and disabilities. These changes, plus global threats such as pandemics, transnational and national security issues, and climate change, mean that regular monitoring of child health and wellbeing is essential if we are to achieve the Sustainable Development Goals. This Health Policy describes the three-phased process undertaken by the Child Health Accountability Tracking technical advisory group (CHAT) to develop a core set of indicators on child health and wellbeing for global monitoring purposes, and presents CHAT's research recommendations to address data gaps. CHAT reached consensus on 20 core indicators specific to the health sector, which include 11 impact-level indicators and nine outcome-level indicators that cover the topics of: acute conditions and prevention; health promotion and child development; and chronic conditions, disabilities, injuries, and violence against children. An additional six indicators (three impact and three outcome) that capture information on child health issues such as malaria and HIV are recommended; however, these indicators are only relevant to high-burden regions. CHAT's four research priorities will require investments in health information systems and measurement activities. These investments will help to increase data on children aged 5-9 years; develop standard metadata and data collection processes to enable cross-country comparisons and progress assessments over time; reach a global consensus on essential interventions and associated indicators for monitoring emerging priority areas such as child development, chronic conditions, disabilities, and injuries; and implement strategies to increase the uptake of data on child health to improve evidence-based planning, programming, and advocacy efforts.

Supporting recommendations for childhood preventive interventions for primary health care: elaboration of evidence synthesis and lessons learnt.

BACKGROUND: Recommendations to prevent morbidity and mortality in children was a high priority for the editorial group of a WHO pocket book for primary health care in the European region. However, the benefit of preventive interventions is not always clear and recommendations differ across countries and institutions. Here, we summarize the existing recommendations and the most recent evidence on ten selected preventive interventions applied to children under five years to inform this group. In addition, we reflect on the process and challenges of developing these summaries. METHODS: For each intervention, we systematically searched for current recommendations from the WHO, the United States Preventive Services Task Force, the workgroup PrevInfad from the Spanish Association of Primary Care Pediatrics, the Centers of Disease Control and Prevention, and the National Institute for Health and Care Excellence. Then, we systematically searched the sources above and the Cochrane library for relevant systematic reviews. For each topic, we reported the recommendations and the strength of the recommendation when and as reported by the authors. We summarized the main findings of systematic reviews with the certainty of the evidence as reported. Categorising the ten preventive interventions in three groups allowed narrative comparisons between similar types of interventions and between groups. RESULTS AND DISCUSSION: For the single interventions of providing vitamins D and K and topical fluoride there is overall a high degree of consensus between institutions for the evidence of their effectiveness. For the multiple interventions to prevent sudden infant death syndrome and unintentional injuries consensus was more variable as evidence of effectiveness is harder to ascertain. For the screening interventions the summaries of recommendations and evidence varied too. While institutions generally agreed in recommending for vision screening and against universal screening for language and speech delay and iron deficiency, they had some differences for pulse oximetry and autism. The transparent and independent process shed light upon how institutions use existing evidence in their settings - common and different positions were accounted for and became visible. We also identified gaps and duplications of research. Our approach was a crucial starting point for developing the respective sections in the pocket book.

Centromedian-Parafascicular and Somatosensory Thalamic Deep Brain Stimulation for Treatment of Chronic Neuropathic Pain: A Contemporary Series of 40 Patients.

Introduction: The treatment of neuropathic and central pain still remains a major challenge. Thalamic deep brain stimulation (DBS) involving various target structures is a therapeutic option which has received increased re-interest. Beneficial results have been reported in several more recent smaller studies, however, there is a lack of prospective studies on larger series providing long term outcomes. Methods: Forty patients with refractory neuropathic and central pain syndromes underwent stereotactic bifocal implantation of DBS electrodes in the centromedian-parafascicular (CM-Pf) and the ventroposterolateral (VPL) or ventroposteromedial (VPM) nucleus contralateral to the side of pain. Electrodes were externalized for test stimulation for several days. Outcome was assessed with five specific VAS pain scores (maximum, minimum, average pain, pain at presentation, allodynia). Results: The mean age at surgery was 53.5 years, and the mean duration of pain was 8.2 years. During test stimulation significant reductions of all five pain scores was achieved with either CM-Pf or VPL/VPM stimulation. Pacemakers were implanted in 33/40 patients for chronic stimulation for whom a mean follow-up of 62.8 months (range 3-180 months) was available. Of these, 18 patients had a follow-up beyond four years. Hardware related complications requiring secondary surgeries occurred in 11/33 patients. The VAS maximum pain score was improved by ≥50% in 8/18, and by ≥30% in 11/18 on long term follow-up beyond four years, and the VAS average pain score by ≥50% in 10/18, and by ≥30% in 16/18. On a group level, changes in pain scores remained statistically significant over time, however, there was no difference when comparing the efficacy of CM-Pf versus VPL/VPM stimulation. The best results were achieved in patients with facial pain, poststroke/central pain (except thalamic pain), or brachial plexus injury, while patients with thalamic lesions had the least benefit. Conclusion: Thalamic DBS is a useful treatment option in selected patients with severe and medically refractory pain.

Revitalizing child health: lessons from the past.

Essential health, education and other service disruptions arising from the COVID-19 pandemic risk reversing some of the hard-won gains in improving child survival over the past 40 years. Although children have milder symptoms of COVID-19 disease than adults, pandemic control measures in many countries have disrupted health, education and other services for children, often leaving them without access to birth and postnatal care, vaccinations and early childhood preventive and treatment services. These disruptions mean that the SARS-CoV-2 virus, along with climate change and shifting epidemiological and demographic patterns, are challenging the survival gains that we have seen over the past 40 years. We revisit the initiatives and actions of the past that catalyzed survival improvements in an effort to learn how to maintain these gains even in the face of today's global challenges.

International medical electives for medical students at a German university: a secondary analysis of longitudinal data.

BACKGROUND: International medical electives (IMEs) are entry points to global health opportunities. IME uptake at German universities is unclear. We analyse 14 y of IME. METHODS: Student registry data were collected. Univariate linear regression examined relationships between enrolment year and IMEs. RESULTS: The median (IQR) number of IMEs of all enrolment years was 54 (32-80) and 51 (38-67)% of all students took an IME. Enrolment year significantly predicted IME frequency and the proportion of students taking IMEs. CONCLUSIONS: Student interest in IMEs is increasing. Universities should invest more broadly in IME opportunities for student, faculty and university enrichment.

The dimensions of "failed back surgery syndrome": what is behind a label?

BACKGROUND: The term failed back surgery syndrome (FBSS) has been criticized for being too unspecific and several studies have shown that a variety of conditions may underlie this label. The aims of the present study were to describe the specific symptoms and to investigate the primary and secondary underlying causes of FBSS in a contemporary series of patients who had lumbar spinal surgery before. METHODS: We used a multilevel approach along three different axes defining symptomatic, morphological, and functional pathology dimensions. RESULTS: Within the study period of 3 years, a total of 145 patients (74 f, 71 m, mean age 51a, range 32-82a) with the external diagnosis of FBSS were included. Disk surgery up to 4 times and surgery for spinal stenosis up to 3 times were the commonest index operations. Most often, the patients complained of low back pain (n = 126), pseudoradicular pain (n = 54), and neuropathic pain (n = 44). Imaging revealed osteochondrosis (n = 61), spondylarthrosis (n = 48), and spinal misalignment (n = 32) as the most frequent morphological changes. The majority of patients were assigned at least to two different symptomatic subcategories and morphological subcategories, respectively. According to these findings, one or more functional pathologies were assigned in 131/145 patients that subsequently enabled a specific treatment strategy. CONCLUSIONS: FBSS has become rather a vague and imprecisely used generic term. We suggest that it should be avoided in the future both with regard to its partially stigmatizing connotation and its inherent hindering to provide individualized medicine.

Global child health in Germany - Time for action.

Child health is central to the SDG agenda. Universities in the UK and other European countries provide leadership in research and education for global child health to inform related policy and practice, but the German contribution is inadequate. German paediatricians and other child health professionals could make more substantial contributions to the debate at home and internationally, but lack opportunities for scholarship and research. We argue, that there is a momentum to advance global child health in academia and call on German universities to realise this potential.

Reappraising the appropriate calculation of a common meteorological quantity: Potential Temperature.

The potential temperature is a widely used quantity in atmospheric science since it is conserved for dry air's adiabatic changes of state. Its definition involves the specific heat capacity of dry air, which is traditionally assumed as constant. However, the literature provides different values of this allegedly constant parameter, which are reviewed and discussed in this study. Furthermore, we derive the potential temperature for a temperature-dependent parameterisation of the specific heat capacity of dry air, thus providing a new reference potential temperature with a more rigorous basis. This new reference shows different values and vertical gradients, in particular in the stratosphere and above, compared to the potential temperature that assumes constant heat capacity. The application of the new reference potential temperature is discussed for computations of the Brunt-Väisälä frequency, Ertel's potential vorticity, diabatic heating rates, and for the vertical sorting of observational data.

Outcomes of Patients Lost to Follow-up in African Antiretroviral Therapy Programs: Individual Patient Data Meta-analysis.

Background: Low retention on combination antiretroviral therapy (cART) has emerged as a threat to the Joint United Nations Programme on human immunodeficiency virus (HIV)/AIDS (UNAIDS) 90-90-90 targets. We examined outcomes of patients who started cART but were subsequently lost to follow-up (LTFU) in African treatment programs. Methods: This was a systematic review and individual patient data meta-analysis of studies that traced patients who were LTFU. Outcomes were analyzed using cumulative incidence functions and proportional hazards models for the competing risks of (i) death, (ii) alive but stopped cART, (iii) silent transfer to other clinics, and (iv) retention on cART. Results: Nine studies contributed data on 7377 patients who started cART and were subsequently LTFU in sub-Saharan Africa. The median CD4 count at the start of cART was 129 cells/µL. At 4 years after the last clinic visit, 21.8% (95% confidence interval [CI], 20.8%-22.7%) were known to have died, 22.6% (95% CI, 21.6%-23.6%) were alive but had stopped cART, 14.8% (95% CI, 14.0%-15.6%) had transferred to another clinic, 9.2% (95% CI, 8.5%-9.8%) were retained on cART, and 31.6% (95% CI, 30.6%-32.7%) could not been found. Mortality was associated with male sex, more advanced disease, and shorter cART duration; stopping cART with less advanced disease andlonger cART duration; and silent transfer with female sex and less advanced disease. Conclusions: Mortality in patients LTFU must be considered for unbiased assessments of program outcomes and UNAIDS targets in sub-Saharan Africa. Immediate start of cART and early tracing of patients LTFU should be priorities.